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We report on the formation of silver nanoparticles by gas aggregation in a reaction chamber at room temperature. The size distribution of nanoparticles deposited on a silicon substrate for various lengths of an aggregation (high-pressure) chamber was investigated by atomic force microscopy. Nanoparticles were characterized by scanning and transmission electron microscopy and spectral ellipsometry. The physical shape of the nanoparticles and its distribution was correlated with their optical properties. Metal–dielectric nanocomposites were deposited employing simultaneous deposition of Ag NPs via high-pressure magnetron sputtering and the dielectric matrix was deposited via thermal evaporation. Pure and Eu-, Er-, and Yb-doped lithium fluoride was used as the dielectric host matrix. Optical transmittance of lithium fluoride containing silver nanoparticles was measured and their theoretical absorption cross-section calculated. The nanoparticles were also embedded in Eu3+-doped downshifting and Er3+- and Yb3+-doped up-conversion materials to study their influence on emission spectra. Spectra of identical layers with and without nanoparticles were compared. Their transmittance at various annealing temperatures is also presented.

Various copper oxide stoichiometries have been grown by Pulsed Laser Deposition (PLD) on MgO (100). The role of oxygen pressure on the structural and physical properties of the films was investigated in the 1·10 –5 Pa – 1 Pa range. Positron annihilation spectroscopy revealed positrons trapped at vacancies and large vacancy clusters with lifetimes ranging from 400 ps to 500 ps. Different stoichiometries were found to be dominated by characteristic vacancies. Single copper vacancies V Cu are found for CuO phase with good indication for p-type applications while for the Cu 2 O complexes of copper vacancies coupled with oxygen vacancies (V Cu + V O and V Cu + 2V O ) are seen. Particular O 2 atmosphere conditions induce a mixture of copper oxide phases with the CuO crystals growing on top of Cu 2 O films. The deposition process was monitored with in situ diagnostic techniques based on optical emission spectroscopy and Langmuir probe method. The kinetics of the plasma during the deposition process are well correlated with the properties of the deposited films. The monitoring tools define clear energetic threshold for the formation of CuO or Cu 2 O phases.

BACKGROUND The mechanisms underlying speech abnormalities in Parkinson's disease (PD) remain poorly understood, with most of the available evidence based on male patients. This study aimed to estimate the occurrence and characteristics of speech disorder in early, drug-naive PD patients with relation to gender and dopamine transporter imaging. METHODS Speech samples from 60 male and 40 female de novo PD patients as well as 60 male and 40 female age-matched healthy controls were analyzed. Quantitative acoustic vocal assessment of 10 distinct speech dimensions related to phonation, articulation, prosody, and speech timing was performed. All patients were evaluated using [123]I-2b-carbomethoxy-3b-(4-iodophenyl)-N-(3-fluoropropyl) nortropane single-photon emission computed tomography and Montreal Cognitive Assessment. RESULTS The prevalence of speech abnormalities in the de novo PD cohort was 56% for male and 65% for female patients, mainly manifested with monopitch, monoloudness, and articulatory decay. Automated speech analysis enabled discrimination between PD and controls with an area under the curve of 0.86 in men and 0.93 in women. No gender-specific speech dysfunction in de novo PD was found. Regardless of disease status, females generally showed better performance in voice quality, consonant articulation, and pauses production than males, who were better only in loudness variability. The extent of monopitch was correlated to nigro-putaminal dopaminergic loss in men (r = 0.39, p = 0.003) and the severity of imprecise consonants was related to cognitive deficits in women (r = -0.44, p = 0.005). CONCLUSIONS Speech abnormalities represent a frequent and early marker of motor abnormalities in PD. Despite some gender differences, our findings demonstrate that speech difficulties are associated with nigro-putaminal dopaminergic deficits.

International audience; Objective: This multilanguage study used simple speech recording and high-end pattern analysis to provide sensitive and reliable noninvasive biomarkers of prodromal versus manifest α-synucleinopathy in patients with idiopathic rapid eye movement sleep behavior disorder (iRBD) and early-stage Parkinson disease (PD).Methods: We performed a multicenter study across the Czech, English, German, French, and Italian languages at 7 centers in Europe and North America. A total of 448 participants (337 males), including 150 with iRBD (mean duration of iRBD across language groups 0.5-3.4 years), 149 with PD (mean duration of disease across language groups 1.7-2.5 years), and 149 healthy controls were recorded; 350 of the participants completed the 12-month follow-up. We developed a fully automated acoustic quantitative assessment approach for the 7 distinctive patterns of hypokinetic dysarthria.Results: No differences in language that impacted clinical parkinsonian phenotypes were found. Compared with the controls, we found significant abnormalities of an overall acoustic speech severity measure via composite dysarthria index for both iRBD (p = 0.002) and PD (p < 0.001). However, only PD (p < 0.001) was perceptually distinct in a blinded subjective analysis. We found significant group differences between PD and controls for monopitch (p < 0.001), prolonged pauses (p < 0.001), and imprecise consonants (p = 0.03); only monopitch was able to differentiate iRBD patients from controls (p = 0.004). At the 12-month follow-up, a slight progression of overall acoustic speech impairment was noted for the iRBD (p = 0.04) and PD (p = 0.03) groups.Interpretation: Automated speech analysis might provide a useful additional biomarker of parkinsonism for the assessment of disease progression and therapeutic interventions. ANN NEUROL 2021;90:62-75.

ZnO:Eu thin film fabricated by pulsed laser deposition was treated by pulsed UV laser. The effect of laser fluence from 70 to 125 mJ cm−2 on film properties was investigated. The results showed that the surface morphology was clearly modified and the film treated at laser fluence of 70 mJ cm−2 was more densified compared to the other annealed films. Laser treatment led to a reduction of carbon content and to a stoichiometric ZnO:Eu composition on the surface. Refractive index significantly decreased and extinction coefficient was blue shifted for higher laser fluences. Strong characteristic Eu3+ transitions were obtained using excitation at 266 nm. The highest photoluminescence intensity was observed for the annealed film at a laser fluence of 70 mJ cm−2. The influence of ambient composition (N2 and O2) and temperature (room temperature and 150 °C) to photoluminescence response was examined for optical gas sensor application. The laser-untreated film showed higher sensitivity to the presence of oxygen at both temperatures compared to the treated film. The stability of photoluminescence intensity at elevated temperature was improved for laser-treated areas.

This paper compares the stress and strain behaviour of mechanical fasteners and elastic adhesive connections in timber façade applications. Two common designs with timber cladding are introduced. The traditional façade planks and multilayer large-format solid wood panels were selected. The resistance of a reference façade section with mechanical fasteners or adhesive bond to wind suction is determined according to the recommendations of European guideline ETAG 034. The pressure/suction chamber allowing hermetic closure was used. The sample deformation was measured at 15 locations, this also allowed to determine the elongation of the adhesive layer at break. The failure loads reached with the adhesive joint exceeded 20 kN/m2in both combinations of façade cladding. On the other hand, the sample with a large-format panel and mechanical fasteners showed the lowest failure load at 12 kN/m2. The results confirmed that bonded joints are a suitable solution for large-format cladding, whereas an increase in the number of mechanical fasteners will be a more convenient solution for façade plank applications.

Single-layered and multi-layered 20–60 nm thick silicon nitride (Si3N4) dielectric nanofilms were fabricated using a low-pressure chemical vapour deposition (LPCVD) method. The X-ray photoelectron spectroscopy (XPS) confirmed less oxygen content in the multi-layered nanofilms. The capacitors with Si3N4 multilayer demonstrated a tendency to a higher breakdown voltage compared to the capacitors with Si3N4 single layer. Si3N4 nanofilms and capacitors with Si3N4 dielectric were exposed to 1 kGy dose of gamma photons. Fourier transform infrared (FTIR) spectroscopy analysis showed that no modifications of the chemical bonds of Si3N4 were present after irradiation. Also, gamma irradiation did not influence the breakdown voltage of the capacitors but decreased their capacitance measured at 1 MHz frequency. However, the multi-layered capacitors were not affected by radiation more than the single-layered capacitors. These findings suggest a promising process to fabricate nano-scaled multi-layered Si3N4 capacitors with improved breakdown voltage characteristics and resistance to ionizing radiation.

Evaluation of precision of consonant articulation is commonly used metric in assessment of pathological speech. However, up to date most of the research on consonant characteristics was performed on English while there are obvious language-specific differences. The aim of the current study was therefore to investigate the patterns of consonant articulation in Czech across 6 stop consonants with respect to age and gender. The database used consisted of 30 female and 30 male healthy participants. Four acoustic variables including voice onset time (VOT), VOT ratio and two spectral moments were analyzed. The Czech plosives /p/, /t/ and /k/ were found to be characterized by short voicing lag (average VOT ranged from 14 to 32 ms) while voiced plosives /b/, /d/ and /g/ by long voicing lead (average VOT ranged from -79 to -91 ms). Furthermore, we observed significantly longer duration of both VOT (p < 0.05) and VOT ratio (p < 0.01) of voiceless plosives in female compared to male gender. Finally, we revealed a significant negative correlation between age and duration of voiceless (r = -0.36, p < 0.05) as well as voiced VOT (r = -0.45, p = 0.01) in female but not in male participants.

Současným trendem při odvodnění vozovek pozemních komunikací je soustředění dešťové vody do podloží vozovek tak, aby se neztrácela v kanalizačních systémech, ale volně se saturovala do podloží. Cílem tohoto výzkumu je optimalizovat konstrukční vrstvy zelených parkovišť při použití zasakovacích roštů AS-TTE. Během návrhu konstrukčních vrstev budou jednotlivé nové typy materiálů včetně podkladních vrstev optimalizovány tak, aby umožnily maximální vsakování vody do podloží a zároveň byly dodrženy požadavky na únosnost konstrukčních vrstev dle ČSN 72 1006. Budou provedeny laboratorní zkoušky zaměřené na základní fyzikálně-mechanické vlastnosti, propustnost vody a adsorpci ropných látek. The current way in drainage of roads is the concentration of rainwater in the subsoil of roads, so that rainwater does not drain into the sewer system, but freely infiltrates into the subsoil. The aim of this research is to optimize the structural layers of green parking lots with AS-TTE grassing blocks. During the design of structural layers and new types of materials, will be optimized to allow maximum water infiltration into the subsoil and at the same time keep the requirements for load-bearing capacity of structural layers according to ČSN 72 1006. Laboratory tests will be performed focusing on basic physical and mechanical properties, water permeability and adsorption of oil drips.

Eu3+-doped oxide thin films possess a great potential for several emerging applications in optics, optoelectronics, and sensors. The applications demand maximizing Eu3+ photoluminescence response. Eu-doped ZnO, TiO2, and Lu2O3 thin films were deposited by Pulsed Laser Deposition (PLD). Pulsed UV Laser Annealing (PLA) was utilized to modify the properties of the films. In situ monitoring of the evolution of optical properties (photoluminescence and transmittance) at PLA was realized to optimize efficiently PLA conditions. The changes in optical properties were related to structural, microstructural, and surface properties characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The substantial increase of Eu3+ emission was observed for all annealed materials. PLA induces crystallization of TiO2 and Lu2O3 amorphous matrix, while in the case of already nanocrystalline ZnO, rather surface smoothening0related grains’ coalescence was observed.

The dynamics of transient plasma generated by UV ns-laser ablation of selected metals (Co, Cu, Ag, Bi) were investigated by the Langmuir Probe method in angle- and time-resolved modes. Multiple ionic and electronic structures were seen for all plasmas with some corresponding to anions or nanoparticle-dominated structures. The addition of an Ar atmosphere energetically confined the plasma and increased the charge density by several orders of magnitude. For pressure ranges exceeding 0.5 Pa fast ions were generated in the plasma as a result of Ar ionization and acceleration in the double layer defining the front of the plasma plume. Several correlations between the target nature plasma properties were attempted. The individual plasma structure expansion velocity increases with the melting point and decreases with the atomic mass while the corresponding charged particle densities decrease with the melting point, evidencing the relationship between the volatility of the sample and the overall abated mass.

Background Impairments of olfactory and speech function are likely early prodromal symptoms of α-synucleinopathy. Objective The aim of this study is to assess whether dysprosody is present in isolated rapid eye movement sleep behavior disorder (iRBD) with hyposmia/anosmia and a normal nigrostriatal system. Methods Pitch variability during speech was investigated in 17 iRBD subjects with normal olfactory function (iRBD-NOF), 30 iRBD subjects with abnormal olfactory function (iRBD-AOF), and 50 healthy controls. iRBD subjects were evaluated using the University of Pennsylvania Smell Identification Test and [123I]-2s-carbomethoxy-3s-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane dopamine transporter single-photon emission computed tomography (DAT-SPECT). All iRBD subjects completed the 24-month follow-up with DAT-SPECT, speech, and olfactory testing. Results At baseline, only iRBD-AOF showed monopitch when compared to iRBD-NOF (P = 0.04) and controls (P = 0.03), with no difference between iRBD-NOF and controls (P = 1). At follow-up, dysprosody progressed only in iRBD-AOF with abnormal DAT-SPECT (P = 0.03). Conclusion Prosody is impaired in hyposmic but not in normosmic iRBD subjects before the nigrostriatal dopaminergic transmission is affected (Braak stage 2). © 2021 International Parkinson and Movement Disorder Society.

The control and arguably the tailoring aspect of technologies like pulsed laser deposition (PLD) rises from understanding the chemistry hidden by the laser generated plasma. With the continuous transition towards thin films with complex structures and geometries, the comprehension of the fundamental processes during the film deposition becomes critical. During the PLD of Mo and Eu-doped Lu2O3, optical emission spectroscopy was implemented for in-situ plasma monitoring. The spatial distribution of individual elements revealed the structuring of a stoichiometric plasma while the formation of LuO molecule within the plasma plume is seen as being induced by the addition of a minimum 1 Pa of O2. The energy of the ejected particles was controlled through doping and O2 pressure. The effect of O2 pressure over the plasma energy revealed a transition from an atomic dominated region towards a molecular dominated one. The properties of the resulted films were analyzed by XRD, AFM, and photoluminescence techniques and show a strong correlation between the dynamical regime of the plasma and their structural properties.

Two 15-membered octaazamacrocyclic nickel(II) complexes are investigated by theoretical methods to shed light on their affinity forwards binding and reducing CO2. In the first complex 1[NiIIL]0, the octaazamacrocyclic ligand is grossly unsaturated (π-conjugated), while in the second 1[NiIILH]2+ one, the macrocycle is saturated with hydrogens. One and two-electron reductions are described using Mulliken population analysis, quantum theory of atoms in molecules, localized orbitals, and domain averaged fermi holes, including the characterization of the Ni-CCO2 bond and the oxidation state of the central Ni atom. It was found that in the [NiLH] complex, the central atom is reduced to Ni0 and/or NiI and is thus able to bind CO2 via a single σ bond. In addition, the two-electron reduced 3[NiL]2− species also shows an affinity forwards CO2.

This article presents an investigation of the sensing properties of chemiresistors based on Cu2O/CuO core–shell nanowires containing p–p′ heterojunctions. The nanowires were synthesized by a conven...

Currently, there is an increase in the number of the world's aging population. This aging process is often connected with cognitive decline of some functions such as memory or speed processing loss. Since Alzheimer's disease cannot be cured yet, considerable efforts are being made to at least delay this cognitive decline among elderly in order to maintain and prolong the quality of their life. This can also be achieved by non-pharmacological approaches such as performing physical activities, cognitive training, or adhering to a Mediterranean Diet (MedDiet). One of the components of MedDiet - extra-virgin olive oil (EVOO) - has considerable health benefits. The purpose of this review is to examine the effect of EVOO intake on the delay of cognitive decline among the elderly. The methodology is based on a literature review of available sources found on the research topic in three acknowledged databases: Web of Science, Scopus, and PubMed. The results of in vitro and in vivo studies indicate that the regular intake of EVOO is associated with enhanced cognitive functions, which means that this oil may have a neuroprotective effect and could positively prevent the development of dementia, especially Alzheimer's dementia. It is believed that secoiridoid oleuropein is responsible for this effectiveness. Furthermore, there is also a need of more randomized controlled studies or longitudinal observational studies to be performed to confirm the efficacy of the beneficial health effect of EVOO on the delay of cognitive decline.

Stacking mismatches in hexagonal boron nitride (h-BN) nanostructures affect their photonic, mechanical, and thermal properties. To access information about the stacked configuration of layered ensembles, highly sophisticated techniques like X-ray photoemission spectroscopy or electron microscopy are necessary. Here, instead, by taking advantage of the geometrical and chemical nature of h-BN, we show how simple structural models, based on shortened interplanar distances, can produce effective charge densities. Accounting these in the non-analytical part of the lattice dynamical description makes it possible to access information about the composition of differently stacked variants in experimental samples characterized by infrared spectroscopy. The results are obtained by density functional theory and confirmed by various functionals and pseudopotential approximations. Even though the method is shown on h-BN, the conclusions are more general and show how effective dielectric models can be considered as valuable theoretical pathways for the vibrational structure of any layered material., Comment: 14 pages, 15 figures, 4 tables. Supplemental Material: 17 pages, 18 figures, 6 tables

The aim of this article is to provide unique and detailed data on how patients rate the RebiSmart 2.0 in the specific User Study Questionnaire (USQ) domains, and the relationship between their rating and individual level of disability, baseline demographic/socioeconomic factors, and adherence. Twelve-month, phase IV, observational, multicenter study (no placebo or comparator) to evaluate the ease of use of the RebiSmart autoinjector for self-injection during treatment of CIS/RRMS subjects with Rebif 44 mcg sc three times a week by USQ. A total of 290 subjects participated in the study, with 249 (85.86%) completing the entire study period. The endpoint results demonstrated a very high proportion (>95%) of patients with a positive evaluation of the overall convenience of RebiSmart at each study visit. At the end of the study, all patients would recommend the device to others who need Rebif therapy. The proportion of patients rating the RebiSmart ease of use by individual domains (self-injection steps, changing the cartridge, using the device away from home) as “very easy to use” or “easy to use” and the proportion of patients rating the RebiSmart functions as “helpful” or “very helpful” were more than 80% for each domain at each study visit. These findings are in line with the potential benefits of RebiSmart to treatment adherence. They demonstrate an overall, very good perception of the device by patients and its individual functions.

The recent advancements in pulsed laser deposition (PLD) control via plasma diagnostics techniques have been positive and raised questions on the limitation of some techniques, such as the Langmuir probe (LP). The particularities of laser-produced plasma can lead to incorrect interpretation of collected electrical signal. In this paper, we explored the limitations of LP as a technique for in situ PLD control by performing investigations on several metallic plasmas, expanding in various Ar atmosphere conditions. Sub-microsecond modulation was seen in the reconstructed IV characteristics attributed to non-equilibrium dynamics of the ejected charges. A perturbative regime was recorded for Ar pressures higher than 2 Pa, where ionic bursts were observed in the electron saturation region. This perturbation was identified as a plasma fireball. A non-linear multifractal model was developed here to explore these new regimes of the LP. The strange attractors characterizing each fireball were reconstructed, and their evolution with the Ar pressure is discussed. Both short- and long-time non-linear behavior were correlated via probe bias, and the pressure effect on the strange attractor’s defining the fireball-like behavior was investigated. A good correlation was noticed between the simulated data and experimental findings.

The continuous effort for transitioning pulsed laser deposition technique from an experimental tool into an industrial one is sustained by the use of complex technologies for in situ real-time monitoring of the deposition process. Floating Langmuir Probe (LP) and optical emission spectroscopy (OES) measurements were used for plasma monitoring during the pulsed laser deposition of Ag films under various Ar pressure conditions. The electrical measurements revealed a complex multi-structured distribution of the ions, which was strongly influenced by the increase of Ar pressure. The generation of highly energetic ions with the addition of Ar and the degree of Ar gas ionization was also explored. OES measurements confirmed the presence of highly ionized Ar species in the plasma. A peculiar effect was seen under pressures higher than 10 Pa, where the presence of high electronic charges lead to a perturbative behavior of plasma in the vicinity of the LP. The effect of these complex dynamics on the structure and quality of the deposited thin film was also investigated revealing a strong correlation between the electronic distribution in plasma and thin film thickness profile.

The aim of this mini-review is to discuss the main antiplatelet agents that have been successfully used in the secondary prevention of non-cardioembolic ischemic stroke and transient ischemic attacks (TIA). The methodology is based on a literature review of available peer-reviewed English studies listed in PubMed. The findings reveal that aspirin remains a reliable antiplatelet agent in the secondary prevention of acute non-cardioembolic ischemic stroke and TIA. Nevertheless, currently, there are also other agents, i.e., ticagrelor, clopidogrel, and cilostazol, that can be applied. In addition, the results indicate that time is significant not only in severe stroke but also in non-severe stroke and TIA, which suggests that antiplatelet therapy should be applied within 24 h after the first symptoms because early treatment can lead to an improvement in neurological outcomes and reduce the chance of an early subsequent stroke.

Building structures have been designed such that they are able to withstand the adverse effects of the environment for a certain time. The terms "for a certain time" and "the surrounding environment" are used for a purpose here, and that is because the phenomenon of ageing buildings is currently an increasingly discussed problem that is faced by every larger city. The materials used in the buildings, such as façade cladding, age just as the buildings themselves do. An immense pressure has been currently put on designers to use environmentally friendly materials not only for new buildings but also for the retrofitting of existing ones. The aim of this paper is to demonstrate that wood or wood composite materials are convenient solution for restoration of façades of administrative or commercial buildings, however, since the new cladding have to be connected with an old load-bearing structure, the designers have to overcome many limitations. One of the main difficulties is high thermal and moisture expansion of these materials which has a direct impact on the appearance of the façade. The obtained results showed that expansion properties should be studied closely when using wooden elements in the design and that a neglection can lead to a premature failure of the system.

Gadolinium bisphthalocyanine (GdPc2) has been placed among the highest ranked molecular materials considered namely for modern optoelectronic applications including organic solar cells. To improve understanding of the correlation between GdPc2 magnetic properties and its electronic functionality, we experimentally and theoretically studied charge carrier concentration, charge mobility, and influence of local magnetic field on charge carrier transport. For better clearance, all the main studied properties of GdPc2 bisphthalocyanine were compared with Zn phthalocyanine (ZnPc) as a reference material. Conductivity and charge carrier mobility were measured in materials incorporated in FET active channels. UV Vis spectroscopy, Electron Paramagnetic Resonance Spectroscopy, and IR spectroscopy were also applied. The narrow band gap together with small ionization potential of GdPc2 lead to high free charge carrier concentration. Among parameters affecting charge carrier mobility, molecular arrangement and intermolecular and intramolecular charge carrier pathways were highlighted. The possibility that the interaction of the mobile charge carriers with the local magnetic field of GdPc2 molecules reduces charge carrier mobility is also discussed.